Dirofilaria immitis and Angiostrongylus vasorum in dogs: epidemiological study in Italy

Dirofilaria immitis and Angiostrongylus vasorum are primary nematodes of dogs. In Europe, the geographical distribution of these parasites is changing due to several factors and a continuous monitoring is essential to increase the knowledge on their epidemiology. The present survey has been carried out to generate updated data on the distribution of dirofilariosis and angiostrongylosis in dogs living in central regions of Italy. Overall, 2000 dogs were included in the study: 400 in Umbria (Site A), 400 in Marche (Site B), 400 in Abruzzo (Site C), 366 in Molise/ Northern Puglia (Site D) and 434 in Lazio (Site E). Dogs were enrolled based on specific inclusion criteria: at least one year of age, not treated for at least six months with molecules effective in the prevention and/or treatment of dirofilariosis and angiostrongylosis and with outdoor access. For each animal fecal and blood samples were collected. All fecal samples were subjected to flotation and Baermann’s test, while blood samples were used to perform the Knott’s test and, if positive for microfilariae, tested with the SNAP test 4DX IDEXX. Overall, 35 dogs (1.7%) were positive for D. immitis, i.e. 16 (4%) in site A, 8 (2%) in site B, 2 (0.6%) in site C, 3 (0.8%) in site D and 6 (1.7%) in site E, while a total of 62 dogs (3.1%) were infected with A. vasorum i.e. 39 (10.2%), 12 (3%), 6 (1.5%), 2 (0.5%), 3 (0.7%) in site A, B, C, D ed E, respectively. These results confirm the occurrence and the spread of D. immitis and A. vasorum in central Italy. Therefore, the present data underlines the importance of a constant vigilance and the need to adopt appropriate preventive strategies both in enzootic and non-enzootic areas, to reduce the spreding of these nematodes and safeguard the health of dogs.